Endograft devices and methods for using the same

ABSTRACT

Various endograft assemblies and methods for using the same. In at least one embodiment of an endograft assembly of the present disclosure, the endograft assembly comprises an endograft and a tube defining one or more tube openings coupled to said endograft. In another embodiment of an endograft assembly of the present disclosure, the endograft assembly comprises an endograft, a sponge sheath coupled to the endograft, and a reservoir bag coupled to the sponge sheath, said reservoir bag capable of receiving fluid from the sponge sheath.

PRIORITY

This U.S. Utility Patent Application is a continuation-in-partapplication of, and claims priority to, copending U.S. patentapplication Ser. No. 11/997,147, filed Jun. 30, 2008, now U.S. Pat. No.8,398,703 which is a U.S. national stage entry of, and claims priorityto, International Patent Application Serial No. PCT/US2006/029424, filedJul. 28, 2006, which claims priority to U.S. Provisional PatentApplication Ser. No. 60/703,421, filed Jul. 29, 2005. The contents ofeach of these applications are hereby incorporated by reference in theirentirety into this disclosure.

BACKGROUND

The present disclosure relates generally to tissue support, includingdevices and methods for magnetic aortic tissue support and for thetreatment of aneurysms.

Aortic aneurysms are formed in a vessel when the wall of the vesselweakens, either due to disease, aging, heredity or some other process.The pressure of the blood flowing through the weakened area causes thevessel wall to balloon out, forming a blood-filled aneurysm sack.Although most aneurysms begin small, they tend to enlarge over time andthe risk of the sack rupturing increases as the aneurysms grows larger.Acute rupture of the aortic aneurysm is a life-threatening event, due tomassive internal bleeding with a mortality rate of 75-80%. According tothe Society of Vascular Surgeons, ruptured aneurysms account for morethan 15,000 deaths in the U.S. each year, making the abdominal aorticaneurysm (AAA) the 13th leading cause of death in the USA. Clearly,early detection and rupture prevention is the key to the final outcomein abdominal aortic aneurysm patient. However, the condition isunder-diagnosed because most patients with AAA are asymptomatic.Consequently, the majority of the anomalies are discovered unexpectedlyduring routine tests or procedures. An estimated 1.7 million Americanshave AAA, but only about 250,000-300,000 patients are diagnosed everyyear.

There is no proven medical treatment for AAA, and surgical repair hasbeen the only common therapeutic option. A standard open repair has beenassociated with significant morbidity and mortality, prolonged recovery,and late complications. Because of these limitations, many patients andtheir physicians choose to defer operative treatment. Recently,endovascular aneurysm repair (EVAR) has become an alternative and somestudies favorably compare endovascular repair with a standard openrepair. However, significant concern exists relating to endovascularrepair and its value is a subject of healthy debate. Endovascularabdominal aortic aneurysm repair has gained acceptance as a minimallyinvasive alternative to open surgery in selected patients. Whilelong-term durability remains uncertain, patients and their physiciansare willing to accept a degree of uncertainty in exchange for dramaticreduction in duration of hospital stay, and need for blood transfusion.Hence, improvements in the current EVAR devices can potentially makethis approach standard for AAA repair.

Most patients diagnosed with AAA are not considered for surgery orendovascular repair unless the aneurysm is at least 5 cm in diameter,the point at which the risk of rupture clearly exceeds the risk ofrepair. Those with a smaller aneurysm are followed closely with regularimaging studies. There has been much speculation over the years aboutthe preventive use of endovascular aneurysm repair in patients withaneurysms smaller than 5 cm, however, vascular surgeons so far have beenreluctant to use EVAR for smaller aneurysms due to the concern about thelong term durability of the technology and the lack of datademonstrating a clear benefit of early intervention. Moreover, althoughEVAR outcomes have improved over the years as physicians gain moreexperience with the procedure, it remains a technically demandingprocedure that requires extensive training and this has limited thenumber of physicians qualified to perform EVAR.

Despite the shortcoming relating to training, a number of endovasculardevices have been evaluated in clinical trials designed to gain approvalfrom governmental agencies. These devices differ with respect to designfeatures, including modularity, metallic composition and the structureof the stent, thickness, porosity, chemical composition of the polymericfabric, methods for attaching the fabric to the stent, and presence orabsence of an active method of fixing the device to the aortic wall withbars or hooks. With consideration of the numbers of structuralvariations between different brands of endovascular devices, it would beremarkable if clinical outcome were not equally dissimilar. Parameterssuch as frequency of endoleak, long-term change in size of the aneurysmsack, reason for device migration and limb thrombosis may be linked tospecific device design features. Hence, any improvements in thedeployment and attachment of stent graft would increase the utility ofEVAR.

Important drivers and limiters of EVAR are playing a big role in thedecision of the treatment. The drivers include: 1) Less invasivecompared to open repair, which translates into shorter hospitalizationand recovery and lower major morbidity; 2) Aging of the population willincrease the incidence and prevalence of AAA and thoracic aorticaneurysm (TAA); 3) Increasingly informed patient population willgenerate strong patient demand for minimally invasive therapy, and 4)Next-generation devices, expected to address wider patient population(including those with thoracic disease) and reduce complicationsrelative to current model. The limiters, on the other hand, include thefollowing: 1) Clinical literature does not support prophylacticendovascular treatment of the small aneurysm with a low risk offracture; 2) High rate of late complication necessitates extensive andpotentially life-long post procedural follow-up (not required for openrepair) and repeat intervention that makes endovascular therapypotentially more costly than open surgery; 3) Current device is notapplicable to full-range of AMA patients; 4) Technical demands of theapproach require devices and time-consuming training that may eliminaterapid adoption of new products, particularly for a specialist with asmaller case load, and 5) Surgical conversion is complicated by thepresence of the stent graft. Improvements in the current devices wouldcertainly make the drivers outweigh the limiters.

The most important trial conducted to date is the EVAR 1 study, whichrandomized over 1,000 elective patients with aneurysms 5.5 cm or largercomparing EVAR to open surgical repair. Thirty-day mortality publishedthis year demonstrated a clear advantage of EVAR (1.6% vs. 4.7% for openrepair). However, EVAR patients had significantly higher rates ofsecondary intervention (9.8% vs. 5.8%). A second version study, EVAR 2,is comparing EVAR with best medical treatment in patients unsuitable forsurgical repair. The 12-month result for EVAR 1 are particularlyimportant, as physicians will be looking to see if endovascular therapyis able, for the first time, to demonstrate significant survival benefitover open surgery after one year.

Despite some of its inherent drawbacks, EVAR is expected to experiencerobust growth over the next several years. The U.S. AAA graft market isprojected to increase from $288 M in 2004 to $552 M in 2008. Inaddition, contribution from thoracic graft systems, beginning this year,will grow the total US aortic stent market to over $670 M in 2008(Endovascular, 2005).

Ongoing areas of concern with endovascular abdominal aortic repairare; 1) Rate of late complications; 2) Appreciable intervention andconversion rates; 3) Dubious cost advantage compared to open surgery dueto the need of intervention and regular patient monitoring; 4) Increaseddevice failure with time; 5) Increased procedural failure with time, and6) Rupture risk of 1% per year after endovascular repair is notdramatically different from the natural history of small 5 cm aneurysms.Hence, there is high rate of secondary intervention (primarily to treatendoleaks—persistent flow within the aneurysm sack that in certain casescan lead to aneurysm rupture, if left untreated), and increasing rate ofdevice failures over time. In addition to endoleaks, other latecomplications in AAA graft trials include device migration, modularcomponent separation, graft thrombosis, bar separation, and materialfatigue.

Currently in the U.S., about 60,000 abdominal aortic aneurysm (AAA)patients require intervention each year. The majority of the patientsare treated with open surgical repair, while about 40% are treated withEVAR. Although open AAA repair is highly successful, it is alsoextremely invasive, with an operative mortality rate between 5-10%.Thus, patients with significant co-morbidities are generally notcandidates for open repair. These patients are the primary beneficiariesof endovascular grafting or EVAR. EVAR gained tremendous popularity in1990 after commercial AAA stent graft became available in the U.S. Aftera one-year period of adjustment, however, problems with the firstgeneration device began to surface including migration, endoleak andendotension. Although physicians remain confident, they have for themost part recovered from the disappointment associated with the firstgeneration technology and are looking forward to future advances in thefield. Further expansion of endovascular repair is required to improvethe device and good long-term results from large randomized trialscomparing EVAR with open surgery. There is no doubt that a device thatovercomes some of the current shortcomings of EVAR devices such asmigration, endoleak and endotension is greatly welcomed for thetreatment of aortic aneurysm.

Thus, a need exists in the art for an alternative to the conventionalmethods of aneurysm treatment. A further need exist for a reliable,accurate and minimally invasive device or technique of treatinganeurysms and minimizing their risks of enlarging or rupturing.

BRIEF SUMMARY

The current EVAR devices and methods are inadequate. They are prone tosuch fatal problems as migration, endoleak, and endotension. In order toaddress this medical problem, the present disclosure provides devicesand methods for minimizing and/or preventing the growth or rupture ofaneurysms or other vascular growth through the use of magnetic tissuesupport.

In at least one embodiment of an endograft assembly of the presentdisclosure, the endograft assembly comprises an endograft having aninner wall, an outer wall, and a graft structure positioned between theinner wall and the outer wall, the inner wall of the endograft definingan endograft lumen sized and shaped to permit fluid to flowtherethrough, and a tube defining one or more tube openings, said tubecoupled to the endograft in a configuration whereby the one or more tubeopenings are exposed along the outer wall of the endograft. In anotherembodiment, the tube is coupled to the outer wall of the endograft. Inyet another embodiment, the tube is coupled to the endograft between theinner wall and the outer wall of the endograft. In an additionalembodiment, the endograft further comprises a length, and wherein thetube extends substantially the length of the endograft.

In at least one embodiment of an endograft assembly of the presentdisclosure, the inner wall of the endograft is impermeable to fluids,and wherein the outer wall of the endograft is permeable to fluids. Inanother embodiment, the endograft assembly further comprises a catheterhaving a distal catheter end, a proximal catheter end, and a lumentherethrough, wherein the distal catheter end of the catheter isremovably coupled to a proximal tube end of the tube. In an additionalembodiment, the endograft assembly further comprises a suction/injectionsource coupled to the catheter at or near the proximal catheter end, thesuction/injection source capable of providing suction within the lumenof the catheter and further capable of injecting a substance into thelumen of the catheter. In yet an additional embodiment, the endograftassembly further comprises a suction/injection source coupled to thecatheter at or near the proximal catheter end, the suction/injectionsource capable of providing suction within the lumen of the catheter tofacilitate removal of blood present within an aneurysm sac when theendograft assembly is positioned within a vessel at or near the site ofa vessel aneurysm and when the catheter is coupled to the tube.

In at least one embodiment of an endograft assembly of the presentdisclosure, the endograft assembly further comprises a suction/injectionsource coupled to the catheter at or near the proximal catheter end, thesuction/injection source capable of injecting a substance into the lumenof the catheter and into an aneurysm sac when the endograft assembly ispositioned within a vessel at or near the site of a vessel aneurysm andwhen the catheter is coupled to the tube. In another embodiment, thesubstance is capable of forming a cast within the aneurysm sac when itis injected to the aneurysm sac, said cast providing structuralreinforcement to the vessel aneurysm. In yet another embodiment, thesubstance is chosen from ethylene vinyl alcohol copolymer, acetatepolymer, ethylene vinyl alcohol dissolved in dimethyl sulfoxide,cellulose, cyanoacrylate, glue, and gel magnetic polymer.

In at least one embodiment of an endograft assembly of the presentdisclosure, the endograft comprises a configuration chosen from astraight configuration and a curved configuration. In an additionalembodiment, wherein the tube comprises a proximal tube end and a distaltube end, and wherein the proximal tube end comprises a tube threadedportion. In yet an additional embodiment, the tube threaded portioncorresponds to a catheter threaded portion located at a distal catheterend of a catheter, permitting the catheter to be rotatably coupled tothe tube. In another embodiment, the catheter further comprises acatheter tip at the distal catheter end, the catheter tip configured tofit within a lumen of the tube. In at least one embodiment of anendograft assembly of the present disclosure, the tube comprises aproximal tube end and a distal tube end, and wherein the proximal tubeend comprises one or more unidirectional valves. In another embodiment,the one or more unidirectional valves permit fluid to flow out of thetube when a catheter is coupled thereto, and wherein the one or moreunidirectional valves prevents fluid from flowing out of the tube when acatheter is not coupled thereto. In yet another embodiment, theendograft assembly comprises one or more materials chosen from nitinol,plastic, polyurethane, silastic, polyvinylchloride, andpolytetrafluoroethylene.

In at least one embodiment of an endograft assembly of the presentdisclosure, the graft structure of the endograft assembly is capable ofa first, collapsed configuration, and is further capable of a second,expanded configuration. In an additional embodiment, the graft structureis chosen from a traditional stent, a balloon-expandable device, or anautoexpandable device. In yet an additional embodiment, the inner wallcomprises a fluid-impermeable fabric, and wherein the outer wallcomprises a fluid-permeable fabric.

In at least one embodiment of an endograft assembly of the presentdisclosure, the endograft assembly comprises an endograft having aninner wall and an outer wall, and a graft structure positioned betweenthe inner wall and the outer wall, the inner wall of the endograftdefining an endograft lumen sized and shaped to permit fluid to flowtherethrough, a tube comprising a proximal tube end, a distal tube end,one or more unidirectional valves at or near the proximal tube end, andone or more tube openings defined along the tube, said tube coupled tothe endograft in a configuration whereby the one or more tube openingsare exposed along the outer wall of the endograft, a catheter having adistal catheter end, a proximal catheter end, and a lumen therethrough,wherein the distal catheter end of the catheter is removably coupled toa proximal tube end of the tube, and a suction/injection source coupledto the catheter at or near the proximal catheter end, thesuction/injection source capable of providing suction within the lumenof the catheter and further capable of injecting a substance into thelumen of the catheter

In at least one embodiment of method for using an endograft assembly ofthe present disclosure, the method comprising the steps of delivering anendograft assembly within a vessel of a patient at or near the site of avessel aneurysm, the endograft assembly comprising an endograft, a tubecoupled to the endograft, the tube defining one or more tube openings, acatheter removably coupled to the tube, and a suction/injection sourcecoupled to the catheter, operating a suction/injection source to removeblood present within an aneurysm sac of the vessel aneurysm, andoperating the suction/injection source to inject a substance into theaneurysm sac to form a cast at or near the site of the vessel aneurysm.In another embodiment, the step of delivering the endograft assemblyfurther comprises the step of deploying the endograft assembly withinthe vessel. In yet another embodiment, the step of operating asuction/injection source to remove blood present within an aneurysm saccauses a wall of the vessel aneurysm to collapse toward the endograftassembly. In an additional embodiment, the substance is capable offorming a cast within the aneurysm sac when it is injected to theaneurysm sac, said cast providing structural reinforcement to the vesselaneurysm.

In at least one embodiment of an endograft assembly of the presentdisclosure, the endograft assembly comprises an endograft having aninner wall and an outer wall, and a graft structure positioned betweenthe inner wall and the outer wall, the inner wall of the endograftdefining an endograft lumen sized and shaped to permit fluid to flowtherethrough, and a sponge sheath having a distal end and a proximalend, the sponge sheath coupled to the outer wall of the endograft andconfigured to permit flow of blood therethrough. In another embodiment,the inner wall of the endograft is impermeable to fluids, and whereinthe outer wall of the endograft is permeable to fluids. In yet anotherembodiment, the sponge sheath defines one or more sponge channelstherein, said sponge channels configured to permit fluid flowtherethrough.

In at least one embodiment of an endograft assembly of the presentdisclosure, the endograft assembly further comprises a reservoir bagcoupled to the sponge sheath at or near the proximal end of the spongesheath, said reservoir bag capable of receiving fluid from the spongesheath and the one or more sponge channels. In another embodiment, theendograft assembly further comprises a catheter having a distal catheterend, a proximal catheter end, and a lumen therethrough, wherein thedistal catheter end of the catheter is removably coupled to thereservoir bag. In yet another embodiment, the endograft assembly furthercomprises a suction/injection source coupled to the catheter at or nearthe proximal catheter end, the suction/injection source capable ofproviding suction within the lumen of the catheter and further capableof injecting a substance into the lumen of the catheter. In anadditional embodiment, the endograft assembly further comprises asuction/injection source coupled to the catheter at or near the proximalcatheter end, the suction/injection source capable of providing suctionwithin the lumen of the catheter to facilitate removal of blood presentwithin an aneurysm sac when the endograft assembly is positioned withina vessel at or near the site of a vessel aneurysm and when the catheteris coupled to the reservoir bag.

In at least one embodiment of an endograft assembly of the presentdisclosure, the endograft assembly further comprises a suction/injectionsource coupled to the catheter at or near the proximal catheter end, thesuction/injection source capable of injecting a substance into the lumenof the catheter and into an aneurysm sac when the endograft assembly ispositioned within a vessel at or near the site of a vessel aneurysm andwhen the catheter is coupled to the reservoir bag. In anotherembodiment, the substance is capable of forming a cast within theaneurysm sac when it is injected to the aneurysm sac, said castproviding structural reinforcement to the vessel aneurysm. In yetanother embodiment, the substance is chosen from ethylene vinyl alcoholcopolymer, acetate polymer, ethylene vinyl alcohol dissolved in dimethylsulfoxide, cellulose, cyanoacrylate, glue, and gel magnetic polymer.

In at least one embodiment of an endograft assembly of the presentdisclosure, the endograft comprises a configuration chosen from astraight configuration and a curved configuration. In anotherembodiment, the reservoir bag comprises a reservoir bag threadedportion. In yet another embodiment, the reservoir bag threaded portioncorresponds to a catheter threaded portion located at a distal catheterend of a catheter, permitting the catheter to be rotatably coupled tothe reservoir bag. In an additional embodiment, the catheter furthercomprises a catheter tip at the distal catheter end, the catheter tipconfigured to fit within a lumen of the reservoir bag.

In at least one embodiment of an endograft assembly of the presentdisclosure, the reservoir bag comprises one or more unidirectionalvalves. In an additional embodiment, the one or more unidirectionalvalves permit fluid to flow out of the reservoir bag when a catheter iscoupled thereto, and wherein the one or more unidirectional valvesprevents fluid from flowing out of the reservoir bag when a catheter isnot coupled thereto. In yet an additional embodiment, the endograftassembly comprises one or more materials chosen from plastic,polyurethane, silastic, polyvinylchloride, and polytetrafluoroethylene.In another embodiment, the endograft assembly is capable of a first,collapsed configuration, and wherein the endograft assembly is capableof a second, expanded configuration. In yet another embodiment, thesponge sheath comprises one or more materials chosen from cellulosefiber, wood fiber, foamed plastic polymer, polyurethane, silastic,rubber, polytetrafluoroethylene, synthetic sponge, natural sponge,low-density polyether, polyvinyl alcohol, and polyester.

In at least one embodiment of an endograft assembly of the presentdisclosure, the endograft assembly comprises an endograft having aninner wall and an outer wall, and a graft structure positioned betweenthe inner wall and the outer wall, the inner wall of the endograftdefining an endograft lumen sized and shaped to permit fluid to flowtherethrough, a sponge sheath having a distal end and a proximal end,the sponge sheath coupled to the outer wall of the endograft andconfigured to permit flow of blood therethrough, the sponge sheathdefining one or more sponge channels configured to permit fluid flowtherethrough, a reservoir bag coupled to the sponge sheath at or nearthe proximal end of the sponge sheath, said reservoir bag capable ofreceiving fluid from the sponge sheath and the one or more spongechannels, a catheter having a distal catheter end, a proximal catheterend, and a lumen therethrough, wherein the distal catheter end of thecatheter is removably coupled to the reservoir bag, and asuction/injection source coupled to the catheter at or near the proximalcatheter end, the suction/injection source capable of providing suctionwithin the lumen of the catheter and further capable of injecting asubstance into the lumen of the catheter.

In at least one embodiment of a method for using an endograft assemblyof the present disclosure, the method comprises the steps of deliveringan endograft assembly within a vessel of a patient at or near the siteof a vessel aneurysm, the endograft assembly comprising an endograft, asponge sheath coupled to the endograft, the sponge sheath defining oneor more sponge channels, a reservoir bag coupled to the sponge sheath,said reservoir bag capable of receiving fluid from the sponge sheath andthe one or more sponge channels, a catheter removably coupled to thereservoir bag, and a suction/injection source coupled to the catheter,operating a suction/injection source to remove blood present within ananeurysm sac of the vessel aneurysm, and operating the suction/injectionsource to inject a substance into the aneurysm sac to form a cast at ornear the site of the vessel aneurysm. In another embodiment, the step ofdelivering the endograft assembly further comprises the step ofdeploying the endograft assembly within the vessel. In yet anotherembodiment, the step of operating a suction/injection source to removeblood present within an aneurysm sac causes a wall of the vesselaneurysm to collapse toward the endograft assembly. In an additionalembodiment, the substance is capable of forming a cast within theaneurysm sac when it is injected to the aneurysm sac, said castproviding structural reinforcement to the vessel aneurysm.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a front view of a magnetically stabilized luminal stentgraft assembly with two magnetic bodies according to an exemplaryembodiment of the present disclosure;

FIG. 2 shows an angled view of a luminal stent graft with a magneticcovering and powder according to an exemplary embodiment of the presentdisclosure;

FIG. 3A shows a front view of a luminal stent graft embedded withmagnetic beads or particles surrounded by a stabilizing magnetic body toprevent distension of the aneurysmic region according to an exemplaryembodiment of the present disclosure;

FIG. 3B shows a cross-section of FIG. 3A to emphasize axial support ofthe diseased region;

FIG. 4 shows T₁₁ changes with a maximum of T₁₁=42.826 KPa (θ=0° and 180°in the inner circular) and minimum of T₁₁=−42.826 KPa (θ=90° and 270° inthe inner circular) according to an exemplary embodiment of the presentdisclosure;

FIG. 5 shows a front view of a luminal stent graft within an aneurysmincorporating a perforated tube for controlling the fluid environmentwithin the aneurysm and an optional pressure sensor as part of atelemetry system according to an exemplary embodiment of the presentdisclosure;

FIGS. 6A-6D show endograft assemblies according to exemplary embodimentsof the present disclosure;

FIG. 6E shows a block diagram of various components of an endograftassembly according to an exemplary embodiment of the present disclosure;

FIG. 7 shows a diagram of a method for using an endograft assemblyaccording to an exemplary embodiment of the present disclosure;

FIGS. 8A-8C show an endograft assembly positioned within a bodily vesselaccording to an exemplary embodiment of the present disclosure;

FIGS. 9A-9C show a connection and disconnection of a removable catheterand a tube of an endograft assembly according to an exemplary embodimentof the present disclosure;

FIG. 10 shows an endograft assembly comprising a sponge sheath accordingto an exemplary embodiment of the present disclosure;

FIGS. 11A-12B show portions of endograft assemblies comprising a spongesheath according to exemplary embodiments of the present disclosure;

FIGS. 13A-13C show a connection and disconnection of a removablecatheter and a reservoir bag of an endograft assembly according to anexemplary embodiment of the present disclosure;

FIG. 14 shows a diagram of a method for using an endograft assemblyaccording to an exemplary embodiment of the present disclosure; and

FIGS. 15A and 15B show an endograft assembly positioned within a bodilyvessel according to an exemplary embodiment of the present disclosure.

DETAILED DESCRIPTION

The disclosure of the present application provides various endograftdevices and methods for using the same. For the purposes of promoting anunderstanding of the principles of the present disclosure, referencewill now be made to the embodiments illustrated in the drawings, andspecific language will be used to describe the same. It willnevertheless be understood that no limitation of the scope of thisdisclosure is thereby intended.

As discussed briefly above, the aneurysm size appears to be the one ofthe most important factors determining risk of aneurysm rupture. Changesin aneurysm dimension have been used as a surrogate marker for clinicalefficacy after endovascular repair. Other morphological changes,including progressive angulation, and aortic neck enlargement, may occurin response to either aneurysm exclusion or associated degenerativechanges in adjacent segments, respectively. In endovascular repair, theaneurysm sack is left intact and, as a consequence, this feature playsan important role in outcome assessment, defining the success or failureof aneurysm exclusion. Long term aneurysm exclusion and devicestabilization is dependent on the maintenance of an effectiveattachment, connection, or seal between the endograft and the hostaorta. Therefore dilatation of the aorta at the site or sites intendedfor primary endograft fixation may lead to treatment failure either withdevice migration or via the occurrence of a new endoleak with aneurysmexpansion. The use of magnets as described in the present disclosure isintended to reduce the neck enlargement and remodeling since the magnetwill distribute the stress more uniformly unlike the stent that posestress concentration which induce vascular remodeling.

Endoleak is defined by the persistence of blood flow outside the lumenof the endoluminal graft but within the aneurysm sack, as determined byan imaging study. An endoleak is evidence of incomplete exclusion of theaneurysm from the circulation and may be the result of an incompleteseal between the endograft and the blood vessel wall, an inadequateconnection between components of a modular prosthesis, fabric defects orporosity, or retrograde blood flow from patent aortic side branches.Hence, an adhesive force at the neck of the stent may minimize orprevent endoleak (type I).

Endoleaks, including their detection, potential clinical significance,and treatment remain an active area of investigation. However, althoughit is now evident that, an endoleak may resolve spontaneously, aproportion of those that do persist have been associated with lateaneurysm rupture. Endoleaks classification include:

-   -   1. Type I:        -   a) Inadequate seal at the proximal end of endograft        -   b) Inadequate seal at the distal end of endograft        -   c) Inadequate seal at the iliac occluder plug    -   2. Type II: Flow from visceral vessels (lumbar, IMA, accessory        renal, Hypogastric) without attachment site connection.    -   3. Type III:        -   a) Flow from module disconnection        -   b) Flow from fabric disruption (Minor<2 mm, Major>2 mm)    -   4. Type IV: Flow from porous fabric (<30 days after graft        placement)

There are also endoleaks of undefined origins where flow is visualizedbut the source is unidentified.

Endotension.

It is now appreciated as AAA may continue to enlarge after endovascularrepair, even in the absence of detectable endoleak, and that thisenlargement may lead to aneurysm rupture. Explanation for persistence orrecurrent pressurization of an aneurysm sack includes blood flow that isbelow the sensitivity limits for detection with current imagingtechnology, or pressure transmission through thrombus, or endograftfabric. On physical examination, the aneurysm may be pulsatile andintrasac measurements may reveal pressure that approach or equal tosystemic values. A magnetic device according to the present disclosurethat provides sufficient “seal” at the two necks of the aneurysm andalong the body of the aneurysm would eliminate endoleaks type and II.

Migration.

Migration is defined by clinical and radiographic parameters, as acaudal movement of the proximal attachment site or cranial movement of adistal attachment site. A device is considered to have migrated if atleast 10 mm of movement was noted relative to anatomic landmarks, apatient experiences a symptom from migration, irrespective of distance,or a secondary intervention was undertaken to remedy migration-relatedproblems, irrespective of distance. An adhesive force with sufficientshear component would also eliminate migration. Hence, one of theadvantages of the present disclosure is the development of amagnet-based anchoring device at the two ends of the graft thatovercomes endoleak and migration.

In biomedical engineering, the electromagnetic effect on biologicalcells has diverse applications such as MRI, bypass surgery, andMEMS-related devices. Static and time-dependent fields are used in thediagnosis and treatment of human disease. MRI involves using a largemagnetic field to image structure. The therapeutic benefits of lowfrequency magnetic fields have been shown to induce gene expression andupregulate the heat shock protein. Recently, magnets are advocated foruse in vascular coupling for distal anastomosis in bypass surgery, whichhas lead to a multi-center clinical trial. To date, most of themagneto-static research on biological cells is investigated by usinganalytic or numerical finite difference methods.

The fundamental equations governing the interaction between current andmagnetic-flux density can be found in any classic textbook. In general,those equations are complex due to the fact that matter possesses agreat variety of properties. For example, if the body of interest iselastic, then a change of shape, volume and temperature can appear.Also, if the sum of all forces acting on the body is not zero,translational or rotational acceleration may occur. Therefore, it isimportant to calculate the Magnetostatic forces and couple theMagnetostatic forces with other physical effects in order to determinethe deformation, rotation, displacement and so on in the matter. In thepresent application, the force balance including the Maxwell's force isanalyzed and simulated based on the distribution of the magnetic-fluxdensity. The coupled formulation of the magnetic field and the surfacestress balance for treatment of aortic aneurysm is demonstrated.

In general, the magnetic field intensity is not curl-free and,therefore, we cannot describe magnetic field intensity in terms of ascalar function. However, there are a number of important applicationsin magnetics in which a magnetic field exists, but there are no currentdensities involved. The most obvious are those involving permanentmagnets. Here we consider a concentric annulus of the stent graftinternal to the vessel lumen and the permanent magnetic ring external tothe vessel wall as shown in FIG. 1. Since the magnetic ring does notcover the entire circumference of the vessel (covers 0 to 270°), thesolution must be numerical. To design the geometry and magneticproperties of the two poles of the magnet (stent and magnetic ring) toproduce the necessary Maxwell force acting on the aortic tissue thatprevents migration, and endoleak.

A three-dimensional Laplace's equation describes the solution for thepotential field in cylindrical coordinates (ρ, Φ, z)

$\begin{matrix}{{\frac{\partial^{2}\Phi}{\partial\rho^{2}} + {\frac{1}{\rho}\frac{\partial\Phi}{\partial\rho}} + {\frac{1}{\rho^{2}}\frac{\partial^{2}\Phi}{\partial\phi^{2}}} + \frac{\partial^{2}\Phi}{\partial z^{2}}} = 0} & (1)\end{matrix}$

The separation of variables is accomplished by the substitution:Φ(ρ,φ,z)=R(ρ)Q(φ)Z(z)

This leads to three ordinary differential equations:

$\begin{matrix}{{\frac{\mathbb{d}^{2}Z}{\mathbb{d}z^{2}} - {k^{2}Z}} = 0} & \left( {3a} \right) \\{{\frac{\mathbb{d}^{2}Q}{\mathbb{d}\phi^{2}} + {v^{2}Q}} = 0} & \left( {3b} \right) \\{{\frac{\mathbb{d}^{2}R}{\mathbb{d}\rho^{2}} + {\frac{1}{\rho}\frac{\mathbb{d}R}{\mathbb{d}\rho}} + {\left( {k^{2} - \frac{v^{2}}{\rho^{2}}} \right)R}} = 0} & \left( {3c} \right)\end{matrix}$The solutions of the first two equations are elementary:Z(z)=e ^(±kz)  (4a)Q(φ)=e ^(±νφ)  (4b)The radial equation can be put in a standard form by the change ofvariable x=kρ. Then it becomes

$\begin{matrix}{{\frac{\mathbb{d}^{2}R}{\mathbb{d}x^{2}} + {\frac{1}{x}\frac{\mathbb{d}R}{\mathbb{d}x}} + {\left( {1 - \frac{v^{2}}{x^{2}}} \right)R}} = 0} & (5)\end{matrix}$This is Bessel's equation, and the solutions are called Bessel functionsof order υ. When υ=m is an integer and k is a constant to be determined.The radial factor isR(ρ)=CJ _(m)(kρ)+DN _(m)(kρ)  (6)Finally, we getΦ(ρ,φ,z)=(Ae ^(±kz))(Be ^(±νφ))[CJ _(m)(kρ)+DN _(m)(kρ)]  (7)where A, B, and C are the unknown constant. If we combine equation (7)and boundary conditions, we can solve any type of magnetic field betweenthe partial (0° to 270°) concentric annulus.

When the distribution of the magnetic field is known, the Maxwell'sstress tensor can be calculated by the following formulation after thecoordinate system transformation from the cylindrical coordinate to therectangular coordinate.

$\begin{matrix}{{T_{ij} = {\frac{1}{\mu}\left\lbrack {{B_{i}B_{j}} - {\frac{1}{2}B^{2}\delta_{ij}}} \right\rbrack}}\left( {{Maxwell`s}\mspace{14mu}{Stress}\mspace{14mu}{Tensor}} \right)} & (8)\end{matrix}$

where T_(ij): Maxwell's stress tensor [N/M², Newton/square meter);δ_(ij): Kronecker delta; B_(j): magnetic-flux density T, Tesla or Wb/m²,weber/meter²]; H_(i)=μB_(i); magnetic field intensity [N/(A·m),weber/(ampere·meter)]; δ_(ij)=1 if i=j; δ_(ij)=0 if i≠j.

In Matrix form,

$\begin{matrix}{{T_{ij} = \begin{bmatrix}{{\mu\; H_{x}^{2}} - {\frac{1}{2}\mu{H}^{2}}} & {\mu\; H_{x}H_{y}} & {\mu\; H_{x}H_{z}} \\{\mu\; H_{x}H_{y}} & {{\mu\; H_{y}^{2}} - {\frac{1}{2}\mu{H}^{2}}} & {\mu\; H_{y}H_{z}} \\{\mu\; H_{x}H_{z}} & {\mu\; H_{y}H_{z}} & {{\mu\; H_{z}^{2}} - {\frac{1}{2}\mu{H}^{2}}}\end{bmatrix}}\left( {{Maxwell`s}\mspace{14mu}{Stress}\mspace{14mu}{Tensor}} \right)} & (9)\end{matrix}$

Once the Maxwell's stress tensor is computed, the equilibrium forcebalance in the surface layer of the artery may be presented.)σ_(ji,j) +T _(ji,j) +f _(i)=0(Equilibrium equation for staticcase)  (10)where σ_(ji) is the stress tensor [N/M², Newton/square meter] and f_(i)is the force [N/M³, Newton/cubic meter].

Once the Maxwell stress is computed, we must calculate the Maxwellforce. Elementary theory relates magnetostatic forces to changes in thetotal magnetic field energy when infinitesimal virtual displacements aremade between magnetic elements.

$\begin{matrix}{F = {\frac{\partial\;}{\partial R}{\int{\frac{B \cdot H}{2}{\mathbb{d}v}}}}} & (11)\end{matrix}$

An alternative method using the Maxwell Stress Tensor allowsmagnetostatic forces to be calculated directly without approximating thelimit of a virtual displacement. Instead, integration of the stresstensor T_(ij) over any surface enclosing the object will give the netforce acting on it directly if we assume that the permeability of thesurrounding tissue (vessel wall and blood) is significantly differentthan that of the permanent magnets. If n is the outward normal to thesurface, the Maxwell force may be computed as follows:F=∫T _(ij) ·nds  (12)Expanding the dot product T_(ij)·n allows the force integral equation(12) to be written explicitly as

$\begin{matrix}{\left. {{\left. {F = {{\frac{1}{\mu_{0}}{\oint{\left\lbrack {B \cdot n} \right)B}}} - {\frac{1}{2}B^{2}n}}} \right\rbrack{\mathbb{d}s}} = {{\mu_{0}{\oint{\left\lbrack {H \cdot n} \right)H}}} - {\frac{1}{2}H^{2}n}}} \right\rbrack{\mathbb{d}s}} & (13)\end{matrix}$The stress vector

$\left. {P = {{{\mu_{0}\left\lbrack {H \cdot n} \right)}H} - {\frac{1}{2}H^{2}n}}} \right\rbrack$does not generally point along H. However for the two extreme cases ofthe H field either normal or parallel to the surface, the forces areeither attractive or repulsive across the surface. But when the fieldcrosses the surface at any other angle than 0° or 90°, there will be ashear component to the force which acts in the plane of the surface When3-D axis migration occurs, the magnetic fields H will change so that theaxis force will be created in order to prevent the migration. Thisrequires numerical method such as the FEM simulation.

An exemplary embodiment of the present disclosure as used in graftassembly 100 is shown in FIG. 1. Assembly 100 includes magnetic bodies110 and magnetic polymer graft 111. In this embodiment, the magneticbodies 110 may be situated at the proximal and distal ends of magneticpolymer graft 111 which may be positioned distal to the renal arteries123 and proximal to the common iliac arteries 122 as shown in FIG. 1.The magnetic bodies 110 may cover part or the entire circumference ofthe abdominal aorta 120. The magnetic bodies 110 are shown to bering-shaped in FIG. 1, but they can be any other shape (e.g.,staple-shaped, etc.) as long as they are able to provide a sufficientmagnetic attractive force on the magnetic polymer graft 111 to stabilizethe magnetic polymer graft 111 on the inner surface of the aorta 120.

The magnetic polymer graft 111 may be situated inside the abdominalaorta 120 or the aneurysmic sack 121 and the magnetic bodies 110 may besituated external to the wall of the abdominal aorta 120 or theaneurysmic sack 121 as shown in FIG. 1. The magnetic bodies 110 may becomposed of a material such that they produce a high magnetic field witha low mass and should be stable against demagnetization. When aferromagnetic material is magnetized in one direction, it will not relaxback to zero magnetization when the imposed magnetizing field isremoved. The amount of magnetization it retains at zero driving field isdefined as remanence. The amount of reverse driving field required todemagnetize it is called coercivity. Some compositions of ferromagneticmaterial will retain an imposed magnetization indefinitely and areuseful as permanent magnets. NdFeB (Neodymium Iron Boron) is an exampleof a permanent magnet used in biological applications includingsutureless vascular anastomosis with magnets.

The magnetic bodies 110 may stabilize the magnetic polymer graft 111 atthe proximal and distal ends of the magnetic polymer graft 111 therebypreventing movement of the magnetic polymer graft 111 or endoleak orendotension. The magnetic polymer graft 111 may be uniformly composed ofa metallic material commonly used in the medical arts such that themagnetic bodies 110 may exert an attractive force on the metallicmaterial such that the magnetic polymer graft 111 is held in position bythe magnetic bodies 110 on the proximal and distal ends of the magneticpolymer graft 1I as illustrated in FIG. 1. Alternatively, the magneticpolymer graft 111 may be composed of metallic material only at itsproximal and distal ends such that the magnetic bodies 110 may beproperly positioned to exert an attractive force on these proximal anddistal ends of magnetic polymer graft 111. In this variation, the bodyof the magnetic polymer graft 111 may be mesh-like and may be composedof any material commonly used in the medical stenting arts (e.g.,polytetrafluorethylene—PTFE) such that it can house the metallicmaterial at its proximal and distal ends. The magnetic polymer graft 111may act as a stent by providing a structural passageway for blood toflow down the abdominal aorta 120 while avoiding contact with theaneurysmic sack 121.

A number of different delivery methods may be used to introduce themagnetic bodies 110 in place. Such methods are also applicable to theother exemplary embodiments presented below. Various delivery methodsinclude, but are not limited to: (a) an abdominal laparoscopic procedure(AAA) or thoracoscopic procedure (TAA); (b) a minimal surgicalprocedure; or (c) an open surgical procedure. Other methods andprocedures are apparent to one having ordinary skill in the art afterconsideration of the present exemplary embodiments and are, thus, withinthe scope of the present disclosure.

Another exemplary embodiment of the present disclosure is presented asassembly 200 and is shown in FIG. 2. Assembly 200 depicts a magneticpolymer graft 211 which includes a magnet cover 212, bonded magnetpowder 213, and a graft lumen 214. The bonded magnet powder 213 of themagnetic polymer graft 211 may be composed of any material commonly usedin the medical magnetic arts. The graft lumen 214 may be formed usingmaterials commonly used in the medical stent arts (e.g.,polytetrafluoroethylene-PTFE). The graft lumen 214 may allow blood topass through its material and thereby prevent contact with the aneurysm(not shown) and it may be of such a diameter as to achieve the optimalor desired volume of blood flow through the aneurysm.

The magnetic polymer graft 211 may interact with magnetic bodies (notshown) situated on the external wall of the abdominal aorta or aorticaneurysm (not shown). In this way, the magnetic polymer graft 213 can beheld in place by the attractive force being exerted on it by themagnetic bodies (not shown). Thus, the bonded magnet powder 213 can besituated inside a magnet cover 212 which may be the external layer ofthe magnetic polymer graft 211. The magnet cover 212 may act to protectand confine the magnet powder 213 and further serve to make contact withthe inside of the abdominal aorta or aortic aneurysm. This configurationwould provide the bonded magnetic powder 213 maximum communication withthe magnetic bodies (not shown) situated on the external wall of theabdominal aorta or aortic aneurysm. The magnetic polymer graft 211 maybe inserted through endovascular procedure into the patient therebyavoiding the complications associated with other invasive techniques.

Yet another exemplary embodiment of the present disclosure as shown ingraft assembly 300 is presented in FIG. 3A. Assembly 300 includesmagnetic body 310 and magnetic polymer graft 311. The magnetic body 310is depicted as being ring-shaped in FIG. 3A but it may be any othershape as described above. The magnetic body 310 may cover part or theentire circumferential surface of the abdominal aorta 320. In the lattercase, the magnetic body 310 may partially ensheathe the abdominal aorta320 such that the magnetic body 310 is provided with enough surface areato interact with the magnetic polymer graft 311 on the inside of theabdominal aorta 320 thereby allowing a sufficient magnetic force to beapplied to the magnetic polymer graft 311. The directional arrows 351illustrate the manner in which the magnetic body 310 may ensheathe theabdominal aorta 320 (e.g., circumferentially) to allow for optimalinteraction between the magnetic body 310 and the magnetic polymer graft311.

FIG. 3B shows a cross-section of assembly 300. The lumen 352 of thegraft 311 may provide a conduit for the blood to flow through theaneurysmic sack (not shown) such that the blood flow does not contactthe aneurysmic sack (not shown). The outer surface of the abdominalaorta 320 may be in physical contact with the magnetic body 310 asillustrated in FIG. 3B. The magnetic polymer graft 311 may make physicalcontact with the inner surface of the abdominal aorta 320 such that themagnetic polymer graft 311 is fitted tightly enough against the innersurface of the abdominal aorta 320 in order to prevent blood leakage outof the graft 311 and into the aneurysmic sack (not shown) via spacebetween the proximal portion of the graft 311 and the inner surface ofthe abdominal aorta 320. This particular embodiment may also preventendoleak type II and may further incorporate magnetic beads or particles363 along the body of graft composite as shown in FIG. 3B, Applicationof magnetic body 310 external to the abdominal aorta 320 in the form ofgel or glue on the adventitial surface may also provide a restrictiveforce which will prevent expansion of aorta against endoleak type II orendotension.

In this embodiment, we may consider the magnetic flux density B, whichplays the significant role in the computation of attraction forces. Themagnetic polymer graft 311 may include, for examples polymer-bondedNd—Fe—B magnets (BNP-8) by compression moulding (polymer-bonding: magnetpowders are mixed with a polymer carrier matrix, such as epoxy). Themagnetic bodies 310 are formed in a certain shape, when the carrier issolidified, which has residual induction Br (0.6-0.65 Teslas or6000-6500 Gauss); the ring consists of, for example, Heusler alloy(Fe₈₀B₂₀), which has the saturation magnetic flux density of 0.1257Teslas (=1257 Gauss); or consists of carbon-coated metal particles,which has saturation magnetization exceeding about 120 emu/g (saturationmagnetic flux density equal to or approximately 0.15 Teslas). Theproperties provide sufficient force to support the abdominal aorta 320.

An exemplary measurement of the stress tension exerted on the bloodvessel and the changes in T₁₁ (Maxwell's stress tensor wherein i=1 andj=1) are shown in FIG. 4 according to an exemplary embodiment of thepresent disclosure. The maximum stress tension is exerted on the vesselat 401 and 403 while the minimum stress tension is exerted on the vesselat 402 and 404 when an exemplary embodiment of the present disclosure isused to stabilize the graft to the inside wall of the vessel by placingmagnetic bodies on the external surface of the vessel. This calculationdemonstrates that the stress levels are within biologically acceptableranges. In other words, the stress distribution demonstrates that thecomputed Maxwell stresses are well within the physiological range oftissue stress and should not harm the tissue. Hence, the presentdisclosure does not overly perturb the vessel wall and should not inducean injury response or remodeling.

Another embodiment of the present disclosure comprises a graft assembly500 as shown in FIG. 5. An exemplary assembly 500, as shown in FIG. 5,includes magnetic bodies 510, magnetic polymer graft 511, tube 515 withtube openings 516, a catheter 517, and an optional pressure sensor 518.Tube 515 with tube openings 516 may function to suck or siphon outaccumulated blood and/or other tissue or matter and to collapse the wallof aneurysmic sack 521 to decrease blood-clot volume, which may reducethe stress in aneurysmic sack 521 after deployment of magnetic bodies510 and decrease the risk of aneurysmic rupture.

Catheter 517 may be connected to tube 515 from the femoral artery suchthat a user is able to suction out accumulated blood and/or othermatter. Alternatively, tube 515 and tube openings 516 may function as anembolization device such that a biocompatible liquid polymer (e.g.,ethylene vinyl alcohol copolymer, cellulose, acetate polymer,cyanoacrylates or glue gel magnetic powder, or the like) may beintroduced into aneurysmic sack 521 via catheter 517 and through tubeopenings 516 in order to pack aneurysmic sack 521 and thereby reduce thepossibility of endoleak or endotension.

Tube 515 may be situated as shown in FIG. 5 on the outer surface ofmagnetic polymer graft 511 in a coiled configuration. Tube 515 may havetube openings 516 situated on the length of tube 515, and may be spacedapart and of such a diameter so that tube openings 516 may optimallyfunction as described above. Additionally, tube openings 516 may be aslit or any other geometric shape including, but not limited to, apyramid, in order to maximize the functioning of tube openings 516 aspreviously described.

In order to ensure efficient deployment of magnetic polymer graft 511and magnetic bodies 510 (e.g., tight seal at the distal and proximalends), it would be desirable to measure pressure in aneurysmic sack 521.An optional pressure sensor 518 may be situated on the outer surface ofmagnetic polymer graft 511 via mounting or gluing. Optional pressuresensor 518 may be in communication with an external telemetry monitoringsystem (not shown) via a wireless communication system (not shown).Optional pressure sensor 518 may be used to indicate whether or not asuccessful deployment of magnetic polymer graft 511 has been achieved.In this case, the measured pressure will yield a pulsatile tracinginitially before deployment of magnetic bodies 510 and magnetic polymergraft 511. Once magnetic bodies 511 secure the proximal and distal endsof aneurysmic sack 521, a tight seal between magnetic bodies 510 and thesurface of aneurysmic sack 521 would eliminate the pulsatile tracing.This would provide indication of successful deployment. This can equallyapply to the current art of stent grafts without magnets.

Optional pressure sensor 518 may also be used to monitor the patient'saneurysm by measuring the pressure within aneurysmic sack 521. It maymonitor the interior pressure of aneurysmic sack 521 by measuring thelocal pressure outside of the wall of magnetic polymer graft 511 andinside the outstretched wall of aneurysmic sack 521. This would be oftremendous clinical value as the physician can monitor the status ofaneurysmic sack 521 and adapt treatment according to aneurysmicbehavior. Currently, expensive and complicated imaging methods (such asMRI and CT) are used to monitor the dimension of the aneurysmlongitudinally at discreet times (annually, etc.). Pressure is morerelevant mechanically as a predictor of rupture and with telemetry itcan be monitored continuously.

An additional embodiment of an endograft assembly of the presentdisclosure is shown in FIG. 6A. As shown in FIG. 6A, endograft assembly600 comprises an endograft 602 having an inner wall 604, an outer wall606, and a graft structure 603 positioned therebetween. Graft structure603, in at least one embodiment, may be mesh-like and may be composed ofany material commonly used in the medical stenting arts (e.g., variouspolymers and metals, including but not limited to PTFE). Graft structure603, in various embodiments, may comprise a traditional stent, aballoon-expandable device, or an autoexpandable device. Inner wall 604and outer wall 606 may comprise a fabric as described herein, or maycomprise one or more other materials capable of permitting orprohibiting fluid flow therethrough as referenced herein. Inner wall 604and outer wall 606 may be positioned a distance from one another, topermit graft structure 603 to be positioned therebetween, and further topermit a tube 515 having tube openings 516 to be positionedtherebetween.

Inner wall 604 also defines an endograft lumen 605, as shown in FIG. 6A,permitting blood flow through a vessel when endograft assembly 600 ispositioned therein, Tube openings 516 within tube 515 are “exposed”along the outer wall 606 of endograft 602, whereby, for example, tube515 has a sealed portion for passing from the walls of endograft 602into a space outside of endograft 602. In another exemplary embodiment,tube 515 is incorporated into outer wall 606 so that tube openings 516of tube 515 are exposed along the outer wall 606. In at least oneembodiment, inner wall 604 is impermeable to fluids (i.e., blood), andouter wall 606 is permeable to fluids, including blood. Endograft 602may comprise any number of additional features that typically oroccasionally accompany endografts.

As shown in FIG. 6A, the proximal end 608 of tube 515 may be removablycoupled to a distal end 610 of removable catheter 612. Asuction/injection source (not shown) may be coupled to the removablecatheter 612 at or near the distal end of removable catheter 612, sothat fluid present in, for example, an aneurysm sac, may be removed byapplying suction to removable catheter 612 so that the fluid may entertube openings 516 of tube 515 as described herein.

Additional embodiments of endograft assemblies 600 of the presentdisclosure are shown in FIGS. 6B-6D. In FIG. 6B, an exemplary endograftassembly 600 is shown in a “collapsed” configuration to permit, forexample, insertion of endograft assembly 600 into a vessel. FIG. 6Cshows an exemplary embodiment of an endograft assembly 600 of thepresent disclosure in an “open” or “deployed” configuration so thatendograft assembly 600 may be used within the body as referenced herein.In at least one embodiment, endograft assembly 600 may be opened ordeployed by way of moving/pulling a portion of endograft assembly 600relative to another portion, similar to the deployment of a stent, sothat graft structure 603 of endograft 602 may expand from a collapsedconfiguration. In at least this example, tube 515 is incorporatedinto/positioned upon outer wall 606, so that tube openings 516 of tube515 are exposed along the outer wall 606 of endograft 602. Such anexemplary endograft assembly 600 may be useful in connection with, forexample, treating an abdominal aortic aneurysm. In addition, and asshown in FIG. 6C, removable catheter 612 is coupled to tube 515, with asealed entrance of tube 515 through the outer wall 606 of endograftassembly 600.

Another exemplary embodiment of an endograft assembly 600 of the presentdisclosure is shown in FIG. 6D. As shown in FIG. 6D, the exemplaryendograft assembly 600 comprises a “curved” configuration, which may beuseful to treat, for example, a thoracic aortic aneurysm. An exemplaryembodiment of an endograft assembly 600 of the present disclosure isshown in FIG. 6E as a block diagram with identified functionalcomponents, wherein said system comprises, for example, an endograft 602comprising a graft structure 603, a tube 515, a removable catheter 612,and a suction/injection source 614 (such as, for example, a syringe).

An exemplary endograft assembly 600, including the endograft assembly600 shown in FIG. 6A, may be used by performing the following method. Anexemplary method 700 for deploying and using an endograft assembly 600of the present disclosure is shown in FIG. 7. As shown in FIG. 7, method700 may comprise the step of delivering endograft assembly 600 to adesired site within a body, including, but not limited, an aneurysm sac(delivery step 702). This step may be performed using any number ofmethods for delivering endografts, stents, and/or other implantabledevices within a human body, so long as removable catheter 612 remainsaffixed to tube 515, so that a suction/injection source 614 coupled toremovable catheter 612 may be used as referenced herein. After endograftassembly 600 is positioned within a vessel, graft portion 603 ofendograft assembly 600 may be opened/deployed from a closed/collapsedconfiguration (deployment step 704) to secure endograft assembly 600within said vessel.

After endograft assembly 600 is deployed within the vessel, suction froma suction/injection source 614 may be used (suction step 706) towithdraw, for example, blood, blood clots, and/or other particulatesfrom an aneurysm sac, by way of blood entering tube openings 516 of tube515 present within/about endograft assembly 600. Performance of suctionstep 704 may also cause the walls of aneurysm sac to collapse aboutendograft assembly 600. The degree to which said walls may collapseabout endograft assembly 600 depends on the relative thickness of saidsac/vessel walls.

After removal of fluid from the area of interest, suction/injectionsource 614 may be used to inject a substance (injection step 708) into,for example, the aneurysm sac. Such a substance may comprise any numberof biocompatible liquids including, but not limited to, various polymerssuch as ethylene vinyl alcohol (EVOH) copolymer, acetate polymer, EVOHdissolved in dimethyl sulfoxide (DMSO), cellulose, cyanoacrylates,various glues, and gel magnetic polymer. Injection of such substancesinto the aneurysm sac would be performed to strengthen/reinforce theweakened aneurysm sac walls (forming a rigid or semi-flexible “cast”) toreduce the likelihood of or prevent aneurysm rupture, which can be fatalin many instances. Said substances may also prevent the migration of anendograft assembly 600 within the vessel by adhering to said assembly600.

After all suction and injection steps have been performed, removablecatheter 612 would be disconnected from tube 515 (catheter disconnectionstep 710) so that the endograft assembly 600 would be separate fromremovable catheter 612. Removable catheter 612 may then be withdrawnfrom the patient's body (catheter withdrawal step 712), allowing theendograft assembly 600, with substance 806 positioned external toassembly 600 to reinforce weakened aneurysm sac walls, to remain withinthe body.

An exemplary embodiment of an endograft assembly 600 of the presentdisclosure is shown in FIGS. 8A-8C. As shown in FIG. 8A, endograftassembly 600 has been inserted, positioned, and deployed within vessel800 at a site of an aneurysm sac 802, which is presumably filled withblood, blood clots, and/or other particulates. The application ofsuction via removable catheter 612 by way of a suction/injection source(not shown) operates to remove the blood, blood clots, and/or otherparticulates, allowing the distended vessel wall 804 to collapse orrevert back to a relatively native configuration as shown in FIG. 8B.Reinforcement of the vessel wall 804 at the site of aneurysm may beperformed by injection step 708 of the method described herein, wherebya substance 806 is injected using suction/injection source throughremovable catheter 612, through tube 515, and out of tube openings 516into the space surrounding endograft assembly 600 at the site ofaneurysm. FIG. 8C depicts this procedure, with the black dotsrepresenting injected substance 806.

FIGS. 9A-9C show exemplary embodiments of a portion of an endograftassembly 600 and at least one embodiment of connecting and disconnectinga tube 515 of endograft assembly 600 to/from removable catheter 612(also referred to as an “intra-stent graft connection”). As shown inFIG. 9A, an exemplary embodiment of a removable catheter 612 maycomprise a catheter tip 900 configured to fit within the internal lumen902 of tube 515. Removable catheter 612, in at least one embodiment, maycomprise a first threaded portion 904 at or near the distal end 610 ofremovable catheter 612, said first threaded portion 904 corresponding toa second threaded portion 906 within tube 515 at or near the proximalend 608 of tube 515. Tube 515, in an exemplary embodiment, may compriseone or more unidirectional valves 908, said valves 908 permitting fluidto flow in and out of tube 515 while removable catheter 612 is coupledthereto (and when unidirectional valves 908 are in a first, openconfiguration), but preventing fluid from flowing out of tube 515 whenremovable catheter 612 is disconnected from tube 515 (and whenunidirectional valves 908 are in a second, closed configuration) asshown in FIG. 9C. Furthermore, and when unidirectional valves 908 are“closed,” blood from the vessel to which endograft assembly 600 ispositioned is prevented from exiting tube 515.

Removal of removable catheter 612 from tube 515 may be performed asshown in FIG. 9B. As shown in FIG. 9B, removable catheter 612 may berotated in a direction indicated by the arrow shown in the figure (orrotated in an opposite direction depending on the configuration of thefirst threaded portion 904 and the second threaded portion 906), wherebysaid rotation would allow removable catheter 612 to detach from tube515, in the direction of the arrow shown in FIG. 9C, permitting removalof removable catheter 612 from the body (at, for example, a patient'sfemoral artery). Rotation of removable catheter 612, as well asoperation of suction/infusion source 614 as referenced herein, may beperformed by a user external to a patient's body.

Additional embodiments of mechanisms for connecting and disconnectingtube 515 from removable catheter 612 are also contemplated by thepresent disclosure. Such mechanisms may include, but are not limited to,pulling removable catheter 612 with enough force to detach removablecatheter 612 from tube 515, magnetic coupling of removable catheter 612to tube 515, and other mechanisms known in the art for connecting anddisconnecting two tubes.

An additional embodiment of an endograft assembly 600 of the disclosureof the present application is shown in FIG. 10. As shown in FIG. 10,endograft assembly 600 comprises an endograft 602 having an inner wall604, an outer wall 606, a graft structure 603 positioned therebetween,and further comprising a sponge sheath 1000 positioned around at least aportion of the outer wall 606 of endograft 602. Inner wall 604 definesan endograft lumen 605, as shown in FIG. 10, permitting blood flowthrough a vessel when endograft assembly 600 is positioned therein. Inat least one embodiment, inner wall 604 is impermeable to fluids (i.e.,blood), and outer wall 606 is permeable to fluids, including blood.Sponge sheath 1000 may comprise any number of biocompatible spongy(porous) materials including, but not limited to, cellulose/wood fibers,various foamed plastic polymers, polyurethane, silastic, rubber, PTFE,synthetic sponges, natural sponges, low-density polyether (also known asthe rainbow packs of non-absorbent sponges), polyvinyl alcohol (PVA),and polyester. Sponge sheath 1000, in at least one embodiment, ispositioned circumferentially around the outer wall 6060 of endograft602, but does not cover either end of said endograft 602.

In at least one embodiment, and as shown in the exemplary embodiment ofthe endograft assembly 600 shown in FIG. 10, one or more sponge channels1002 are defined within sponge sheath 1000. Sponge channels 1002 may, asshown in the exemplary embodiment shown in FIG. 10, have open distalends 1004 at or near the distal end 1006 of endograft 602, and theproximal ends 1008 of sponge channels 1002, at or near the proximal endof endograft 602, are in fluid communication with a reservoir bag 1010coupled to sponge sheath 1000. Sponge channels 1002 may be parallel toone another (as shown in FIG. 10), or may comprise a perpendicular,radial, or net configuration. Reservoir bag 1010 may be collapsible, andmay comprise any number of materials as referenced herein in connectionwith various endograft assemblies and/or components.

Additional embodiments of exemplary endograft assemblies 600 (andportions thereof) of the present disclosure are shown in FIGS. 11A-11C.As shown in FIG. 11A, the exemplary endograft assembly 600 comprises anendograft 602 comprising a graft structure 603, a sponge sheath 1000(identified by the numerous ovals to visually depict the pores of asponge), and a reservoir bag 1010 coupled thereto. The endograftassembly 600 shown in FIG. 11A is shown in a collapsed configuration topermit, for example, insertion of endograft assembly 600 into a vessel.FIG. 11B shows an exemplary embodiment of an endograft assembly 600 ofthe present disclosure in an open or deployed configuration so thatendograft assembly 600 may be used within the body as referenced herein.The exemplary endograft assembly is also shown in FIG. 11B with aremovable catheter 612 removably coupled to reservoir bag 1010, so thatblood removed from the aneurysm cavity from sponge sheath 1000 thatenters reservoir bag 1010 may be removed using removable catheter 612.

A portion of an exemplary endograft assembly 600 of the presentdisclosure is shown in FIG. 11C. As shown in the portion of endograftassembly 600 shown in FIG. 11C, endograft assembly 600 comprises anendograft 602 comprising a graft structure 603, a sponge sheath 1000,and sponge channels 1002 having distal ends 1004 at the distal end 1006of endograft 602.

Additional embodiments of portions of exemplary endograft assemblies 600of the present disclosure are shown in FIGS. 12A and 12B. As shown inFIG. 12A, endograft assembly comprises an endograft 602 surrounded by asponge sheath 1000. At the distal end of endograft 602, sponge channels1004 are visible within sponge sheath 1000 as shown in FIG. 11C. FIG.12B shows a portion of an exemplary endograft assembly 600, whereby areservoir bag 1010 is coupled to a sponge sheath 1000 at or near theproximal end 1200 of endograft assembly 600. A removable catheter 612 isalso shown in FIG. 12B coupled to reservoir bag 1010, Removable catheter612 may be removably coupled to reservoir bag 1010 in the same orsimilar manner as removable catheter 612 is coupled to tube 515 as shownin FIGS. 9A-9C, or removable catheter 612 may be removably coupled toreservoir bag 1010 as referenced below.

FIGS. 13A-13C show exemplary embodiments of a portion of an endograftassembly 600 and at least one embodiment of connecting and disconnectinga reservoir bag 1010 of endograft assembly 600 to/from removablecatheter 612. As shown in FIG. 13A, an exemplary embodiment of aremovable catheter 612 comprises a catheter tip 900 configured to fitwithin the internal space 1300 of reservoir bag 1010. Removable catheter612, in at least one embodiment, may comprise a first threaded portion904 at or near the distal end 610 of removable catheter 612, said firstthreaded portion 904 corresponding to a second threaded portion 1302within reservoir bag 1010. Reservoir bag 1010, in an exemplaryembodiment, may comprise one or more unidirectional valves 1304, saidvalves 1304 permitting fluid to flow in and out of reservoir bag 1010while removable catheter 612 is coupled thereto (and when unidirectionalvalves 1304 are in a first, open configuration), but preventing fluidfrom flowing out of reservoir bag 1010 when removable catheter 612 isdisconnected from reservoir bag 1010 (and when unidirectional valves1304 are in a second, closed configuration) as shown in FIG. 13C.Furthermore, and when unidirectional valves 1304 are closed, blood fromthe vessel to which endograft assembly 600 is positioned is preventedfrom exiting reservoir bag 1010. In addition, and as shown in FIGS.13A-13C, a stent graft wall 1306 may be positioned at or near theportion of reservoir bag 1010 to receive removable catheter 612, wherebystent graft wall 1306 provides reinforcement so that reservoir bag 1010does not collapse about removable catheter 612.

Removal of removable catheter 612 from reservoir bag 1010 may beperformed as shown in FIG. 13B. As shown in FIG. 13B, removable catheter612 may be rotated in a direction indicated by the arrow shown in thefigure (or rotated in an opposite direction depending on theconfiguration of the first threaded portion 904 and the second threadedportion 1302), whereby said rotation would allow removable catheter 612to detach from reservoir bag 1010, in the direction of the arrow shownin FIG. 13C, permitting removal of removable catheter 612 from the body(at, for example, a patient's femoral artery). Rotation of removablecatheter 612, as well as operation of suction/infusion source 614 asreferenced herein, may be performed by a user external to a patient'sbody.

Additional embodiments of mechanisms for connecting and disconnectingreservoir bag 1010 from removable catheter 612 are also contemplated bythe present disclosure. Such mechanisms may include, but are not limitedto, pulling removable catheter 612 with enough force to detach removablecatheter 612 from reservoir bag 1010, magnetic coupling of removablecatheter 612 to reservoir bag 1010, and other mechanisms known in theart for connecting and disconnecting a tube from a reservoir.

An exemplary endograft assembly 600, including the endograft assemblies600 shown in FIGS. 10-13C, may be used by performing the followingmethod. An exemplary method 1400 for deploying and using an endograftassembly 600 of the present disclosure is shown in FIG. 14. As shown inFIG. 14, method 1400 may comprise the step of delivering endograftassembly 600 to a desired site within a body, including, but notlimited, an aneurysm sac (delivery step 1402). This step may beperformed using any number of methods for delivering endografts, stents,and/or other implantable devices within a body known in the art, so longas removable catheter 612 remains affixed to reservoir bag 1010, so thata suction/injection source 614 coupled to removable catheter 612 may beused as referenced herein. After endograft assembly 600 is positionedwithin a vessel, graft portion 603 of endograft assembly 600 may beopened/deployed from a closed/collapsed configuration (deployment step1404) to secure endograft assembly 600 within said vessel.

After endograft assembly 600 is deployed within a vessel, suction from asuction/injection source 614 may be used (suction step 1406) towithdraw, for example, blood, blood clots, and/or other particulatesfrom an aneurysm sac, by way of blood entering sponge channels 1002 ofsponge sheath 1000 present around endograft assembly 600, enteringreservoir bag 1010, and exiting out of removable catheter 612.Performance of suction step 1404 may also cause the walls of aneurysmsac to collapse about endograft assembly 600, which depends on therelative thickness of said sac/vessel walls.

After removal of fluid from the area of interest, suction/injectionsource 614 may be used to inject a substance (injection step 1408) into,for example, the aneurysm sac. Such a substance may comprise any numberof biocompatible liquids including, but not limited to, various polymerssuch as ethylene vinyl alcohol (EVOH) copolymer, acetate polymer, EVOHdissolved in dimethyl sulfoxide (DMSO), cellulose, cyanoacrylates,various glues, and gel magnetic polymer. Injection of such substancesfrom removable catheter 612, through sponge sheath 1000, and into theaneurysm sac would be performed to strengthen/reinforce the alreadyweakened aneurysm sac walls (forming a cast) to reduce or prevent thelikelihood of aneurysm rupture, which can be fatal in many instances.Said substances may also prevent the migration of an endograft assembly600 within the vessel by adhering to said assembly 600.

After all suction and injection steps have been performed, removablecatheter 612 would be disconnected from reservoir bag 1010 (catheterdisconnection step 1410) so that the endograft assembly 600 would beseparate from removable catheter 612. Removable catheter 612 may then bewithdrawn from the patient's body (catheter withdrawal step 1412),allowing the endograft assembly 600, with a substance 806 positionedexternal to assembly 600 to reinforce weakened aneurysm sac walls, toremain within the body.

Use of an exemplary endograft assembly 600 consistent with method 1400is shown in FIGS. 15A and 15B. As shown in FIG. 15A, endograft assembly600 is positioned within a vessel 800 at the site of an aneurysm(identified by aneurysm sac 802 and distended vessel wall 804). Uponremoval of blood from aneurysm sac 802 (via suction step 1406, forexample) through sponge sheath 1000, into reservoir bag 1010, and outfrom removable catheter 612, one or more substances 806 may be injectedinto aneurysm sac 802 as shown in FIG. 15B (via injection step 1408, forexample). The injected substance 806 (represented by the black dots inFIG. 15B) may form a cast as referenced herein, reinforcing the vesselwalls 804 at the site of an aneurysm.

Several advantages to such an exemplary endograft assembly 600 includethe following. First, the collapsible sponge sheath 1000 of endograftassembly 600, positioned closely to the external surface of endograft602, may vary its volume according to the size of its pores and mayoccupy some or all of the aneurysm sac cavity. The pores within spongesheath 1000 may facilitate the removal of blood content from theaneurysm sac cavity to enter sponge sheath 1000, thus collapsing theaneurysm sac wall about endograft assembly 600. The combination ofsponge sheath 1000 (with its inherent pores) and sponge channels 1002allow relatively easy removal of blood from the aneurysm sac and theinjection of substances into the aneurysm sac with low resistance.Furthermore, the collapsible sponge sheath 1000 may be useful for allEVAR endoprosthesis procedures in order to form a cast around theendograft assembly 600, filling the aneurysm sac, and avoiding manycomplications such as migration, endoleak, and structural alterations ofendograft 602 produced by the stress-stretching pressure wall effect.

The various endograft assemblies 600, as well as components coupledthereto, may comprise any number of suitable medical grade materials,including, but not limited to, nitinol, various plastics, polyurethane,silastic, polyvinylchloride (PVC), and polytetrafluoroethylene (PTFE).

As shown in the various embodiments of endograft assemblies 600 of thepresent disclosure, said assemblies 600 are configured to permit bloodflow through the vessel for which they are placed. Said endograftsystems 600 also have the additional advantage of being used in all EVARendoprosthesis procedures in order to perform a cast around theendograft assembly 600, filling the aneurysm sac and avoiding severalcomplications such as Endoleak I and II and structural alterations ofthe endograft assembly 600 produced by the stress stretching pressurewall effect.

Endograft assemblies 600 of the present disclosure may be deliveredand/or positioned within a vessel lumen using any number of medicaltools known in the art to deliver stents and/or endografts.

Although the above exemplary embodiments of the present disclosure aredescribed in connection with treatment of aneurysms, particularly anabdominal aortic aneurysm, the disclosure of the present application isnot limited to its use in correcting aneurysms. Many other uses arepossible within the scope of the present disclosure. For example, thecombination of a metallic material and a corresponding magnetic devicemay be used for the correction of the structure or architecture oforgans, such as the heart or along other parts of the aorta or othervessels.

While various embodiments of devices and methods for treating aneurysmshave been described in considerable detail herein, the embodiments aremerely offered by way of non-limiting examples of the disclosuredescribed herein. It will therefore be understood that various changesand modifications may be made, and equivalents may be substituted forelements thereof, without departing from the scope of the disclosure.Indeed, this disclosure is not intended to be exhaustive or to limit thescope of the disclosure.

Further, in describing representative embodiments, the disclosure mayhave presented a method and/or process as a particular sequence ofsteps. However, to the extent that the method or process does not relyon the particular order of steps set forth herein, the method or processshould not be limited to the particular sequence of steps described.Other sequences of steps may be possible. Therefore, the particularorder of the steps disclosed herein should not be construed aslimitations of the present disclosure. In addition, disclosure directedto a method and/or process should not be limited to the performance oftheir steps in the order written. Such sequences may be varied and stillremain within the scope of the present disclosure.

The invention claimed is:
 1. An endograft assembly, comprising: anendograft having an inner wall, an outer wall, and a graft structurepositioned between the inner wall and the outer wall, the inner wall ofthe endograft defining an endograft lumen sized and shaped to permitfluid to flow therethrough; and a tube defining one or more tubeopenings, said tube positioned at least partially around the endograftand positioned upon the outer wall so that the one or more tube openingsare exposed outward relative to the outer wall of the endograft andwherein the tube is coupled to the endograft between the inner wall andthe outer wall of the endograft; the endograft configured to reinforceweakened aneurysm sac walls and to remain within a vessel of a patientafter being positioned therein and used to inject a substance into ananeurysm sac of the vessel to form a cast therein.
 2. The endograftassembly of claim 1, wherein the endograft further comprises a length,and wherein the tube extends substantially the length of the endograft.3. The endograft assembly of claim 1, wherein the inner wall of theendograft is impermeable to fluids, and wherein the outer wall of theendograft comprises a material that itself is permeable to fluids. 4.The endograft assembly of claim 1, further comprising a catheter havinga distal catheter end, a proximal catheter end, and a lumentherethrough, wherein the distal catheter end of the catheter isremovably coupled to a proximal tube end of the tube.
 5. The endograftassembly of claim 4, further comprising a suction/injection sourcecoupled to the catheter at or near the proximal catheter end, thesuction/injection source capable of providing suction within the lumenof the catheter and further capable of injecting a substance into thelumen of the catheter.
 6. The endograft assembly of claim 4, furthercomprising a suction/injection source coupled to the catheter at or nearthe proximal catheter end, the suction/injection source capable ofproviding suction within the lumen of the catheter to facilitate removalof blood present within an aneurysm sac when the endograft assembly ispositioned within a vessel at or near the site of a vessel aneurysm andwhen the catheter is coupled to the tube.
 7. The endograft assembly ofclaim 4, further comprising a suction/injection source coupled to thecatheter at or near the proximal catheter end, the suction/injectionsource capable of injecting a substance into the lumen of the catheterand into an aneurysm sac when the endograft assembly is positionedwithin a vessel at or near the site of a vessel aneurysm and when thecatheter is coupled to the tube.
 8. The endograft assembly of claim 7,wherein the substance is capable of forming a cast within the aneurysmsac when it is injected to the aneurysm sac, said cast providingstructural reinforcement to the vessel aneurysm.
 9. The endograftassembly of claim 8, wherein the substance is chosen from ethylene vinylalcohol copolymer, acetate polymer, ethylene vinyl alcohol dissolved indimethyl sulfoxide, cellulose, cyanoacrylate, glue, and gel magneticpolymer.
 10. The endograft assembly of claim 1, wherein the endograftcomprises a configuration chosen from a straight configuration and acurved configuration.
 11. The endograft assembly of claim 1, wherein thetube comprises a proximal tube end and a distal tube end, and whereinthe proximal tube end comprises a tube threaded portion.
 12. Theendograft assembly of claim 11, wherein the tube threaded portioncorresponds to a catheter threaded portion located at a distal catheterend of a catheter, permitting the catheter to be rotatably coupled tothe tube.
 13. The endograft assembly of claim 12, wherein the catheterfurther comprises a catheter tip at the distal catheter end, thecatheter tip configured to fit within a lumen of the tube.
 14. Theendograft assembly of claim 1, wherein the tube comprises a proximaltube end and a distal tube end, and wherein the proximal tube endcomprises one or more unidirectional valves.
 15. The endograft assemblyof claim 14, wherein the one or more unidirectional valves permit fluidto flow out of the tube when a catheter is coupled thereto, and whereinthe one or more unidirectional valves prevents fluid from flowing out ofthe tube when a catheter is not coupled thereto.
 16. The endograftassembly of claim 1, wherein the endograft assembly comprises one ormore materials chosen from nitinol, plastic, polyurethane, silastic,polyvinylchloride, and polytetrafluoroethylene.
 17. The endograftassembly of claim 1, wherein the graft structure of the endograftassembly is capable of a first, collapsed configuration, and is furthercapable of a second, expanded configuration.
 18. The endograft assemblyof claim 1, wherein the graft structure is chosen from a traditionalstent, a balloon-expandable device, or an autoexpandable device.
 19. Theendograft assembly of claim 1, wherein the inner wall comprises afluid-impermeable fabric, and wherein the outer wall comprises afluid-permeable fabric.
 20. An endograft assembly, comprising: anendograft having an inner wall and an outer wall, and a graft structurepositioned between the inner wall and the outer wall, the inner wall ofthe endograft defining an endograft lumen sized and shaped to permitfluid to flow therethrough; a tube comprising a proximal tube end, adistal tube end, one or more unidirectional valves at or near theproximal tube end, and one or more tube openings defined along the tube,said tube positioned at least partially around the endograft andpositioned upon the outer wall so that the one or more tube openings areexposed outward relative to the outer wall of the endograft and whereinthe tube is coupled to the endograft between the inner wall and theouter wall of the endograft; a catheter having a distal catheter end, aproximal catheter end, and a lumen therethrough, wherein the distalcatheter end of the catheter is removably coupled to a proximal tube endof the tube; and a suction/injection source coupled to the catheter ator near the proximal catheter end, the suction/injection source capableof providing suction within the lumen of the catheter and furthercapable of injecting a substance into the lumen of the catheter; theendograft configured to reinforce weakened aneurysm sac walls and toremain within a vessel of a patient after being positioned therein andused to inject a substance into an aneurysm sac of the vessel to form acast therein.
 21. The endograft assembly of claim 20, wherein theendograft further comprises a length, and wherein the tube extendssubstantially the length of the endograft.
 22. The endograft assembly ofclaim 20, wherein the inner wall of the endograft is impermeable tofluids, and wherein the outer wall of the endograft comprises a materialthat itself is permeable to fluids.
 23. The endograft assembly of claim20, wherein the substance is capable of forming a cast within theaneurysm sac when it is injected to the aneurysm sac, said castproviding structural reinforcement to the vessel aneurysm.
 24. Theendograft assembly of claim 23, wherein the substance is chosen fromethylene vinyl alcohol copolymer, acetate polymer, ethylene vinylalcohol dissolved in dimethyl sulfoxide, cellulose, cyanoacrylate, glue,and gel magnetic polymer.
 25. The endograft assembly of claim 20,wherein the endograft comprises a configuration chosen from a straightconfiguration and a curved configuration.
 26. The endograft assembly ofclaim 20, wherein the tube comprises a proximal tube end and a distaltube end, and wherein the proximal tube end comprises a tube threadedportion.
 27. The endograft assembly of claim 26, wherein the tubethreaded portion corresponds to a catheter threaded portion located at adistal catheter end of a catheter, permitting the catheter to berotatably coupled to the tube.
 28. The endograft assembly of claim 27,wherein the catheter further comprises a catheter tip at the distalcatheter end, the catheter tip configured to fit within a lumen of thetube.
 29. The endograft assembly of claim 20, wherein the tube comprisesa proximal tube end and a distal tube end, and wherein the proximal tubeend comprises one or more unidirectional valves.
 30. The endograftassembly of claim 29, wherein the one or more unidirectional valvespermit fluid to flow out of the tube when a catheter is coupled thereto,and wherein the one or more unidirectional valves prevents fluid fromflowing out of the tube when a catheter is not coupled thereto.
 31. Theendograft assembly of claim 20, wherein the endograft assembly comprisesone or more materials chosen from nitinol, plastic, polyurethane,silastic, polyvinylchloride, and polytetrafluoroethylene.
 32. Theendograft assembly of claim 20, wherein the graft structure of theendograft assembly is capable of a first, collapsed configuration, andis further capable of a second, expanded configuration.
 33. Theendograft assembly of claim 20, wherein the graft structure is chosenfrom a traditional stent, a balloon-expandable device, or anautoexpandable device.
 34. The endograft assembly of claim 20, whereinthe inner wall comprises a fluid-impermeable fabric, and wherein theouter wall comprises a fluid-permeable fabric.
 35. A method for using anendograft assembly, the method comprising the steps of: delivering anendograft assembly within a vessel of a patient at or near the site of avessel aneurysm, the endograft assembly comprising: an endograft, a tubepositioned at least partially around the endograft, the tube definingone or more tube openings, wherein the tube is positioned upon the outerwall so that the one or more tube openings are exposed outward relativeto the outer wall of the endograft and wherein the tube is coupled tothe endograft between the inner wall and the outer wall of theendograft, a catheter removably coupled to the tube, and asuction/injection source coupled to the catheter; operating thesuction/injection source to remove blood present within an aneurysm sacof the vessel aneurysm; operating the suction/injection source to injecta substance into the aneurysm sac to form a cast at or near the site ofthe vessel aneurysm; and reinforcing weakened aneurysm sac walls byallowing the endograft assembly to remain within the vessel after thestep of operating the suction/injection source to inject the substanceinto the aneurysm sac.
 36. The method of claim 35, wherein the step ofdelivering the endograft assembly further comprises the step ofdeploying the endograft assembly within the vessel.
 37. The method ofclaim 35, wherein the step of operating a suction/injection source toremove blood present within an aneurysm sac causes a wall of the vesselaneurysm to collapse toward the endograft assembly.
 38. The method ofclaim 35, wherein the substance is capable of forming a cast within theaneurysm sac when it is injected to the aneurysm sac, said castproviding structural reinforcement to the vessel aneurysm.
 39. Anendograft assembly, comprising: an endograft having an inner wall beingimpermeable to fluids, an outer wall comprising a material that itselfis permeable to fluids, and a graft structure positioned between theinner wall and the outer wall, the inner wall of the endograft definingan endograft lumen sized and shaped to permit fluid to flowtherethrough; and a tube defining one or more tube openings, said tubepositioned at least partially around the endograft and positioned uponthe outer wall so that the one or more tube openings are exposed outwardrelative to the outer wall of the endograft and wherein the tube iscoupled to the endograft between the inner wall and the outer wall ofthe endograft; the endograft configured to reinforce weakened aneurysmsac walls and to remain within a vessel of a patient after beingpositioned therein and used to inject a substance into an aneurysm sacof the vessel to form a cast therein.
 40. The endograft assembly ofclaim 39, wherein the endograft comprises a configuration chosen from astraight configuration and a curved configuration.
 41. The endograftassembly of claim 39, wherein the tube comprises a proximal tube end anda distal tube end, and wherein the proximal tube end comprises a tubethreaded portion.
 42. The endograft assembly of claim 39, wherein thetube comprises a proximal tube end and a distal tube end, and whereinthe proximal tube end comprises one or more unidirectional valves. 43.An endograft assembly, comprising: an endograft having an inner wall, anouter wall, and a graft structure positioned between the inner wall andthe outer wall that is capable of a first, collapsed configuration, anda second, expanded configuration, the inner wall of the endograftdefining an endograft lumen sized and shaped to permit fluid to flowtherethrough; and a tube defining one or more tube openings, said tubepositioned at least partially around the endograft and positioned uponthe outer wall so that the one or more tube openings are exposed outwardrelative to the outer wall of the endograft and wherein the tube iscoupled to the endograft between the inner wall and the outer wall ofthe endograft; the endograft configured to reinforce weakened aneurysmsac walls and to remain within a vessel of a patient after beingpositioned therein and used to inject a substance into an aneurysm sacof the vessel to form a cast therein.
 44. The endograft assembly ofclaim 43, wherein the endograft comprises a configuration chosen from astraight configuration and a curved configuration.
 45. The endograftassembly of claim 43, wherein the tube comprises a proximal tube end anda distal tube end, and wherein the proximal tube end comprises a tubethreaded portion.
 46. The endograft assembly of claim 43, wherein thetube comprises a proximal tube end and a distal tube end, and whereinthe proximal tube end comprises one or more unidirectional valves. 47.An endograft assembly, comprising: an endograft having an inner wall, anouter wall, and a graft structure positioned between the inner wall andthe outer wall and that is chosen from a traditional stent, aballoon-expandable device, or an autoexpandable device, the inner wallof the endograft defining an endograft lumen sized and shaped to permitfluid to flow therethrough; and a tube defining one or more tubeopenings, said tube positioned at least partially around the endograftand positioned upon the outer wall so that the one or more tube openingsare exposed outward relative to the outer wall of the endograft andwherein the tube is coupled to the endograft between the inner wall andthe outer wall of the endograft; the endograft configured to reinforceweakened aneurysm sac walls and to remain within a vessel of a patientafter being positioned therein and used to inject a substance into ananeurysm sac of the vessel to form a cast therein.
 48. The endograftassembly of claim 47, wherein the endograft comprises a configurationchosen from a straight configuration and a curved configuration.
 49. Theendograft assembly of claim 47, wherein the tube comprises a proximaltube end and a distal tube end, and wherein the proximal tube endcomprises a tube threaded portion.
 50. The endograft assembly of claim47, wherein the tube comprises a proximal tube end and a distal tubeend, and wherein the proximal tube end comprises one or moreunidirectional valves.